First, it sounds like you need to match your stepper voltage to your supply, I.e. 12v stepper needs 12v supply. The driver does nothing but pass that through a current chopper and then to the stepper. To answer your question, the driver allows 750mA per winding, so if you set it on max (or min if you have the backwards screen printing), you can hope it will chop the current well enough to limit it, but I wouldn’t count on it. You should really just buy a high-power H-Bridge to drive your stepper.

I would NOT suggest this. if you are looking to drive more current, use a H-Bridge. Using this to drive a MOSFET may very easily fry the board. Neither a MOSFET nor an H-Bridge will provide the current and thermal protection that this board does, and will not do the micro stepping.

It just needs to use either 3.3 or 5V for control input, the Pi uses 3.3V, so you have to do a very simple modification to the board, should be on the website for it (http://www.schmalzhaus.com/EasyDriver/), other than that, it will work fine.

Even if they weren’t ripped off, micro USB is flawed in design. the connector itself wears out after repeated use. I’ve had it happen on a number of phones, after daily plug/unplug the male pins just stop making a connection. SparkFun made the right choice. This is a larger board, go with the larger, safer connector.

I’m finding this to be true. I’m using a 1A H-Bridge and it is getting REALLY hot, in well under 10s of idle. SparkFun really needs to review this and test their products! All it is really doing is help them sell their own motor driver or fry these motors, which is not fair to the customer.

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